Refrigerating apparatus



Oct. 7, 1958 J. WElBEL,-JR 2,355,139

REFRIGERATING APPARATUS Filed June 23, 1955 5 Sheets-Sheet 1 INVENTOR.John Weibe/ Jr.

His Aftorhey Oct. 7, 1958 I J. WEIBEL, JR 2,855,139

REFRIGERATING APPARATUS Filed June 23, 1955 5 Sheets-Sheet 2 Fig. 3

INVENTOR. John Weibel Jr.

His Attorney.

Oct. 7, 1958 J. WEIBEL, JR 2,855,139

REFRIGERATING APPARATUS Filed June 23, 1955 5 Sheets-Sheet 3 'INVENTOR.John Weibe/ Jr.

H is Attorney Oct. 7, 1958 Filed June 25, 1955 J. WEIBEL, JR

REFRIGERATING APPARATUS 5 Sheets-Sheet 4 INVENTOR. John Weibe/ Jr.

. WWW

His Attorney REFRIGERATING APPARATUS John Weibel, Jr., Dayton, Ohio,assignor to General Motors Corporation, Detroit, Mich., a corporation ofDelaware Application June 23, 1955, Serial No. 517,603 i 4 Claims. ((31.230-58) This invention relates to refrigerating apparatus and moreparticularly to a hermetically sealed motorcompressor assembly.

It is an object of this invention to provide a low cost direct connectedreciprocating compressor which may be manufactured on a mass productionbasis.

Another object of this invention is to provide a motor compressorassembly having an improved bearing arrangement which simplifies theproblem of assembling the parts.

Still another object of this invention is to provide an improved oilpump arrangement for supplying oil to the compressor mechanism and themain drive shaft.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to, the accompanyingdrawings, wherein a preferred form of the present invention is clearlyshown.

In the drawings:

Figure 1 is a vertical sectional view taken substantially on line 1-1 ofFigures 3 and 4 showing one embodiment of the invention;

Figure 2 is a perspective view with parts broken away of the compressorshown in Figure 1;

Figure 3 is a fragmentary sectional view taken substantially on line 3-3of Figure 1;

Figure 4 is a sectional view taken substantially on line 44 of Figure 1;

Figure 5 is a fragmentary pictorial view with parts broken away showingthe lower bearing and oil pump construction;

Figure 6 is a fragmentary sectional view showing the oil pump;

Figure 7 is an exploded view with parts broken away showing themotor-compressor assembly; and

Figure 8 is an elevational view with parts broken away showing analternative arrangement for supporting and enclosing the motor andcompressor mechanism.

Referring to the drawings wherein preferred embodiments of the inventionhave been shown, reference numeral 10 generally designates one form ofouter shell for enclosing the motor and compressor assembly generallydesignated by the reference numeral 12. The casing 10 consists of anupper inverted cup-shaped member 14 which serves as the main support forthe motorcompressor assembly and a lower cup-shaped element 16 which iswelded to the element 14 along the seam 18. Suitable mounting brackets20 are secured to the lower cup-shaped element 16 for supporting theentire assembly on a suitable support which has not been shown.

The upper shell 14 has secured to its inner walls mounting lugs 22 whichserve to support the main casting 24. A special mounting bracket 23 hasits ends secured to two of the lugs 22 and this bracket serves tosupport two of the lugs 27 of the main casting 24 at the two spacedpoints as shown in Figures 3 and 4. Resilient rubber like mounting pads25 are provided for damping the vibrations and bolts 29 hold the casting24 in place on the lugs 22.

2,855,139 Patented Oct. 7, 1958 The main casting 24 in turn supports themotor stator 26 in the manner shown. The casting 24 also supports abearing 28 in which the main drive shaft 30 is journalled. The bearingelement 28 is held in place within a machined circular recess providedin the main support 24 by means of a split ring element 32. As shown inFigure 1 of the drawing the split ring is beveled so as to cam thebearing 28 downwardly. The motor rotor 34 is securedto the upper end ofthe drive shaft 30 in accordance with conventional practice. The lowerend of the drive shaft 30 is journaled in a lower bearing portion 36provided as a part of the main casting or frame 24.

An offset crank like portion 38 is provided on the drive shaft 30 andserves to operate a pair of connecting rods 40 which drive the pistons42 in accordance with well known practice. A pair of counterweights 44are secured to the offset portion of the drive shaft as shown for thepurpose of balancing the crank shaft. The main casting 24 is providedwith a pair of cylinder bores 46 in which the pistons 42 operate.Cylinder heads and valve plates 48 and 50 respectively are bolteddirectly to the casting 24 opposite the cylinder bores 46 in accordancewith well known practice.

The gas to be compressed is supplied to the casing 10 through thesuction line 52 which is arranged as best shown in Figures 1, 2 and 4.It will be noted that this suction line enters the upper portion of theshell 14 and that a screen 54 is provided for screening out any sedimentor the like which may be supplied along with the gas and lubricantthrough the line 52. The incoming mixture of gas and lubricant is dumpeddirectly into the outer shell 10 and is required to flow upwardly aroundthe motor stator and then to flow downwardly through the motor. Holes 56are provided in the motor rotor so as to help cool the motor.

The gas then flows downwardly through passages 60 (see Figures 3 and 7)formed in the casting 24 and then into communicating drilled holes orpassages 62, through holes 63 in the valve plates 50 which convey thegas into the chamber 64 provided in each of the cylinder heads 48. Thegas then flows through the usual suction port 66 and around the flexingreed 67 into the cylinder where the gas is compressed before beingdischarged through the corresponding outlet port 68 and outlet valve 69into the outlet chamber 70 in the cylinder head. The outlet chamber '70in each cylinder head communicates with hole 71 in the valve plate andpassages 72 in the casting 24 which lead to the common muffler chamber74 provided directly in the main casting 24. A cap 77 closes the bottomof the chamber 74. The compressed refrigerant leaves the chamber 74through the passage 75 in the main casting and the outlet line 76 whichpasses through the wall of the upper shell portion 14 as best shown inFigures 2 and 4 of the drawings.

The construction and arrangement of the cylinder head and the inlet andoutlet ports and valves carried by the valve plate 50 is intended torepresent conventional construction which needs no further descriptionas the construction thereof is well known to those skilled in the art.The arrangement of the gas passages within the main casting 24, however,is novel in that the incoming gas serves to cool vital parts of themotor-compressor assembly and a minimum number of pipe connections arenecessary with the construction shown.

The main frame 24 is cast in one piece and the critical machinedsurfaces for supporting the rotating parts may be machined while thecasting is held in a single chunk so that the motor stator supportingsurface 80, the main bearing supporting surface 82 and the bottombearing surface 84 will be concentric.

An oil pump which will pump oil irrespective of the direction ofrotation of the motor is provided for supply- 3 ing lubricant underpressure to the various bearing surfaces of the motor compressor unitthrough passage means 85 in the main drive shaft 30. This pump ismounted adjacent the lower end of the main drive shaft 30 and consistsof--a vane-86 which is arranged in'aslot 87 in the bottom surfaceof theshaft 30. This vane operates within a pumping chamber formed between theshaft and a 'mainoil pump body element 88 which also serves asa pumpreversing ring. This ring is mounted for limited rotational movementwithin an enlargement 90 in the lower end ofxthe main-casting 24'and=isprovided with a -pair of-cut-away portions 92 and 94 which selectivelyserve as inlet-and outlet ports'for thepumping chamber'which is formedby' the clearance between the shaft -30-and the ring element88.

In the position of the parts shown in Figure 6' of the drawing-thecut-away portion 92 is arranged in alignment with the oil-inlet opening96 formed in the side wall of the lower end'of the main casting 24 andthe cut-away portion 94 serves as the outlet port' and is arranged inalignment-with-the oil outlet passage 98. Upon reversal of direction ofoperation of themain shaft 30 the reversing ring 88 will be shifted soas to cause thecut-away portion 94 to lineup with the oil inlet 100 asshown'in Figure 4 and the cut-away portion 92 will line up with the oiloutlet 98. The reversing ring 88 is prevented from rotating more than alimited amount by a stop pin 102carried by the casting 24. This pinprojects down into a cut-away portion 104 in the one edge of thereversing ring 88 as shown.

The frictional drag between the rotating parts carried by the shaft 30and the reversing ring 88 is relied upon to shift the ring 88 uponreversal of rotation of the main drive shaft. As best shown in Figure 1of'the drawing the lower end of the shaft 30 and the bottom surface ofthe'vane 86press against a plate thrust bearing 106 and this plate triesto rotate with the shaft due to the friction between the two but theplate is secured to the reversing ring 88 so as to be limited in itsrotation after it has shifted the reversing ring into one or the otherof its extreme positions. A bottom oil pump cover and end thrust bearingelement 108 is secured to the lower end of the main casting 24 by meansof one or more bolts such as the bolt 110 shown in Figure 5. This endthrust member 108 is provided with a small central thrust projection 112which presses against the central bottom surface of the disc 106. Byvirtue of the fact that the area of contact between the projection 112and the disc 106 is much less than the area of contact between the shaftand the disc it is obvious that the disc will try to rotate with theshaftat all times'and will assist in properly positioning'the reversingring.

By virtue of the arrangement shown and described herein it is possibleto assemble the parts by inserting the drive shaft downwardly throughthe central cavity of the frame 24 after the pistons and connecting rodshave been pushed into place. It will also be noted that each of thecounter weights 44 has an'aperture 45 thru which the 'shaftmay be passedduring assembly of the parts. .The entire designlends itself to quickand accurate assembly and alignment of the various elements with aminimum number and most simple form of fastening means for holding theparts assembled.

Figure 8 shows analternative arrangement for supporting and e'nclosingthe motor and compressor mechanism and in this-arrangement the samemotor-compressor mechanism is used but a different type of housing isused for enclosing the motor-compressor mechanism. In the modificationshown in Figure 8, the compressor parts are supported within the lowercup-shaped housing element 150 to which a suitable mounting base 151 issecured for supporting the entire assembly on a support (not shown). Thehousing 150 is a stamped sheet metal housing which is formed with flatledges 152- on which spring type compressor mounts 154 rest. Thesespring mounts engage 4 the mounting lugs 27 provided on the maincompressor casting 24. The upper portion'of the housing consists of aninverted cup-shaped element 156 which is also a stamped sheet metalmember which is are welded to the lower cup-shaped element along themeeting edges as indicated at 158.

The only difference between the motor-compressor mechanism shown inFigures 1 through 7 and the motorcompressor mechanism shown'in Figure 8is that the main drive shaft 30 has been .made longer so as to projectabove the motor rotor and stator as shown. The upper housing element 156is provided with-an inverted cupshaped element160 which is arranged tohave its lower rim surround the shaft 30. This cup 160 will serve tolimit the sidewise movement of theupper end of the motor-compressorassembly during shipment so as to prevent damage to any of the parts inthe case of any severe jolt. It will be noted that in this modificationthe motor terminals 162 are carried'by theupper shelli portion 156 andthat they are arranged'in close proximity to the upper end of the motorstator windings. It'will' also benoted that in this modification therefrigerant outlet line 166..is secured to the lower cup shaped element150 by a clamp 153 and is wrapped around the main casting 24 so as toprovide a longer length tubing between the compressor outlet and thepoint where the line '166'leaves.the compressor housing. This increasedlength of line is provided because of theincreasedamount of vibrationwhich results' fromusing spring mounts of the type .shown in Figure 8 ascompared'with the rubber mounts shown in the compressor in Figures 1through 7.

While the form of embodiment of the invention as herein disclosedconstitutes a preferred form, it is to be understood that other formsmight be adopted, as may come withinthe scope of'the claims whichfollow.

What is claimed is as follows:

. 1. In a motor-compressor unit, a. main frame, a vertically disposedshaft journaled in said frame, a 'motor 'drivingly connected to theupper part of said shaft, compressor means drivingly connected to anintermediate portion of said shaft, and an oil pump drivingly connectedto the lower portion of said shaft, an endthrust bearing element carriedby said frame adjacent the lower end of said shaft, 21 housing forenclosing said motor, said compressor means and oil pump, spring meansfor supporting said main frame in said housing, the upper end of saiddrive shaft projecting above said.motor, and means carried by saidhousing surrounding said uppersprojecting end of saiddrive.shaftforlimiting sidewisernove ment of said drive shaft.

2. Refrigerating .apparatus comprising: .a .casing, a main framesupported withinnsaidcasing, a.motorsupported. on said frame, saidmotorincluding a vertically disposed main drive shaft compressor meanssupported in said-mainv frame and operated bysaid .driveshaft, saidframe having. bearing surfaces engaging-saiddrive shaft, an oil pump.driven bysaiddrivesh'aft, said oil pump comprising an impeller supportedby.-Jsaid drive shaft, meanscooperating with saidimpellenand forming apumping chamber having inlet and outlet port means,

said pumping chamber including a port: reversing element surface smallerthan the-cross sectional area of said shaft, said means forming apumping chamber including a disc secured to said reversingelementandlsupported between said surface and the end of said shaft.

. 3. In a motor-compressor unit, amain frame, a vertically disposedshaft journaledin said. frame, amotor.drivingly connected to .an upperportion of .said .shaft, cornpressor means drivingly connected to anintermediate portion of said shaft, and an oil pump drivingly connectedto the lower portion of said shaft, an end thrust hearing elementcarried by said frame adjacent the lower end of said shaft, a discinteiposed between said end thrust bearing element and the lower end ofsaid shaft, said disc having a larger area of contact with said shaftthan with said end thrust bearing element, said pump including meansforming a pumping chamber having inlet port means and outlet port meansand means for interchanging the functions of said port means in responseto a change in the direction of rotation of said shaft, said last namedmeans comprising an element secured to said disc.

4. In a motor-compressor unit, a main frame, a vertically disposed shaftjournaled in said frame, bearing means for said shaft, a motor drivinglyconnected to the upper end of said shaft, compressor means drivinglyconnected to an intermediate portion of said shaft, and an oil pumpdrivingly connected to the lower portion of said shaft for supplying oilto said bearing means, an end thrust bearing element carried by saidframe adjacent the lower end of said shaft, a disc interposed betweenReferences Cited in the file of this patent UNITED STATES PATENTS861,626 Young July 30, 1907 2,483,007 Higham Sept. 27, 1949 2,490,391Wentling Dec. 6, 1949 2,565,077 Hol-l Aug. 21, 1951 2,628,016 HighamFeb. 10, 1953 2,741,425 Scheldorf Apr. 10, 1956 2,751,146 Moseley June19, 1956

